I looked at differences in the viscocity at 100 for m1 and edge. The edge has a much lower visc of any the other 5w30's on the lower end of the 30 range. M1's about avg. Is this good? I know the GC 0w30 is closer to a 40w via this 100 visc measurement so any ideas why edge would use a lower thickness other than maybe fuel economy?